Preheat oven to 375 degrees F.,In a small bowl, whisk together the balsamic, olive oil, minced garlic and honey.,Season generously with salt and fresh ground pepper.,(Dont be shy with the salt, peeps.),Set aside briefly while you prepare the chicken.,Rinse chicken with cold water, making sure that the cavity is empty and clean, and pat it dry.,Place the lemon quarters, smashed garlic cloves and the basil (reserving 3-4 leaves to place under the skin) into the cavity.,Use your fingers to carefully separate the chicken skin from the breasts, being careful not to rip the skin.,______,Pour 1 1/2 tablespoons of the balsamic dressing under the skin and rub it over the breasts.,Arrange a few basil leaves under the skin as well.,Place the chicken in a roasting pan or a cast iron skillet and pour 2/3 of the remaining dressing over the chicken.,Use your hands to rub it all over the chickens skin.,(Kinda messy and gross, but necessary.),Turn the chicken on its side and transfer it to the oven.,Roast the chicken for 20 minutes.,Carefully turn the chicken onto its other side (I recommend using tongs for this), baste it with some of its juices, and roast for another 20 minutes.,While the chicken is in the oven, place the tomatoes, mushrooms and onions in a large bowl and add the remaining dressing.,Toss to coat and set aside.,Turn the chicken breast side up and baste it with some more juice.,Surround the chicken with the tomatoes, mushrooms and onions and tent loosely with foil.,(This chicken tends to darken quickly thanks to the balsamic.),Return to the oven and roast for another 20 minutes.,Remove the foil and roast for another 15 minutes or until a meat thermometer inserted into the thickest part of the thigh reads 165 degrees F. Remove the chicken from the pan and let it rest for 20 minutes before carving.,While the beautiful balsamic chicken is resting, place the pan with the vegetables and juices over medium-high heat and simmer until the liquid is reduced and thickened slightly, about 10 minutes.,Serve chicken warm topped with tomatoes, mushrooms and onions.,I like to serve mine over some fresh arugula.